Electrical contact pad



Nov. 29, 1932.

G. A, zERNE 1,889,271

ELECTRICAL CONTACT PAD Filed April 22, 1931 Patented Nov. 29, 1932 In, UNITED STATES parlarmi OFFICE eus/rnv, A. zERNnor BROOKLYN, NEW Yonx ELECTRICAL' CONTACT PAD Abpncation mea april 22,

vide apad of the character indicated with a` metal facing having specialfacilities for bey ing instantly removed and replaced with another facing which at alltimes makes per- '15 fect contact'with the electrodes vand with the skin.

There is alsoanother object of equal importance involved inl providing a metal clamping plate for the contact pad whose form is such as to efficientlyretain a rubber cushion which serves asa resilient backing for the metal facing, and also serves to hold said facing in place when once set in position. Anotherobject is to provide the metal fac'- ing Vwith means for Vengaging beneath the edges of the Vclamping plate whereby to retain said facingover the cushion of the pad without dangerof its lbecoming disengaged by.

the outward pressure exerted by the cushion .30 from within the clamping plate.

It is alsoan object of my invention to make a contact pad withv a sanitary' facing which may be discarded after each' treatment, by which a new treatment facing is assured to eachpatient. 4 l

Further objectsand the various advantages inherent in my inventionwill appear more fully in .detail as this specification proceeds.

. In the accompanying drawing, -Fig. 1 is a general view of a diathermy clamp wherein two contact pads are included which arezmade according to the main features of: my invention and embody the same in practical form. v l v j Fig. 2 is a view of one of the contact pads in dissassembled condition,w0r just prior to putting the metal facing in place. Y

Fig.; 3,isv ano-ther view'of the same `pad when partly assembled, showing the manner ofplacing the facing into position.`

1931. serial No. 531,998.

Fig. 4 is a modification ofFig. 3, showing another facing.

Fig. 5 is a view of a modification o-f the contact pad when the cushion has a dierent form. y l

Fig. 6 is a modification of the diathermy clamp with somewhat modified contact pads for gripping smaller objects, such as fingers, etc., the former clamp being more adapted foruse when treating` arms, legs, elbows or shoulders, etc. 9 l

Throughout the various views, the same Vreference numerals indicate the same or corresponding parts.

It iscustomary for practitioners in diathermy and electrotherapeutics to apply water, or soap solution,lather, or similar aqueous applications to the mesh facing 'of diathermy pads used in clamps familiar to the art when about toplace the said pads in contact with the skin of a patient, whereafter currents of various qualities anddegrees are passed through the member of the patient clamped between the pads. It has been found by experience thatl such pads be# come foul and insanitary after a short period of use, due toy the fact that the metal mesh facin'gis very difficult to remove, re'- sulting4 also incorrosion of the same, which makes for poor contacts and sometimes abruptshocls and irregularity inthe passage of the currents through the mesh. In other words, the pads break down in a short time andbecome both disgusting, insanitary and ineffective, so that they must be bodily discarded, although representing no small outlay on the equipment list., if

It has been with the object in view of elimi-v nating the named disadvantages as well as Y including the aforesaid objects that the present invention was designed. f

In the Vpractice of my invention, a diathermy clamp, generally indicated at 1 has the usualy construction in regard to the insulate bar 2 upon which a pair of clamping arms 3, 3 are slidable so long as no object is being clamped between.- the arms or j aws', as'theyy may also` be termed. As well known,

this general type of clamp will hold any ob` ject between its lower ends when thearms are pushed toward each other, for they then begin to bind on the bar 2. However, this is no actual part of this invention, but mentioned to provide a proper background for the contact pad about to be minutely described.

Near the lower ends 4, 4 of the clamping arms 3,3 are pivoted a pairv of clamping plates, generally indicated by 8, 8, the latter being mounted upon posts 6, 6 which are hollow to receive the contact points 16, 16 ofthe current wires or cords 17 17. Each clamping plate has a curved back 10 whose middle portion is depressed to receive the shoulder 7 of the post 6, while the ends are bent over to form retainingedges 12, 12. The plate is adapted to swivel on its post 6, so that it may be turned tomost useful position at will. lA softY cushion of sponge rubber oro-ther suitable material 15 is placed into the clamping plate, and, due to its expansive properties, will -iill the space between the retaining edges 12, 12, and between the same will project in a bulging-curve, as seen in Fig. 2 without any `facing thereon. The cushion itself is, of course retained in assembly with the plate owing to the 1form of the latter preventing the escape of the cushion therefrom. If now a metal facing is to be putinto place upon the cushion, this is not. done as ordinarily, that is, the facing, often a chain mesh of some kind is placed about the cushion and the ends clamped or screwed down or o-therwise permanently xed in place. Instead, it is preferred to use a lengthY of tinfoil, or the like as at 13, and a pair of retaining bars or tubes 11, 11, and first layone bar upon the end of the foil and press Vsaid end with they bar enveloped therein under one retaining edge 12 of the clamping plate, after which the same is done at the other end, and the foil is held at both ends while the `cushion holds the intermediate portion up to conform with its shape. It may sometimes,be-desirable to have a more .prominent cushion such as 20vin Fig. 5, where the cushion projects more fully at the ends immediately withinthe retaining edges12, 12, this ensuring a greater sur face contact with the patientsskin if the parts to be treated are very convex. Then again, it may also be useful to have a ymetal chain mesh 18 instead of the thin metal foil, and in this case, the ends of the mesh may be linked directly to a rod or a coil spring 19 which is merely pushed down under the retaining edge 12, and the same will hold the mesh in place by virtue of the pressure of the rubber cushion. The whole front of the pad 8 is soft and yielding so that if two suchl contact pads are fitted into the clamp as shown in Fig. 1, the pads may resiliently clam a limb between them, as indicated at 14. Y en the treatment is terminated, the foil can readily be removed by individually pulling inward each end to release the same, and another piece of foil then placed in the pad structure. It is obvious that the currents pass from cords 17, 17 through points 16, 16 intoI the posts 6, 6 and plates 10, 10 and retaining edges 12, 12, and thence into the foil 13, 13, from which the same pass into the member treated. t

Upon occasion, only a finger or two requires treatment, and then a smaller clamp shown in Fig. 6 is suitable, operating on the same general principles. The usual insulate bar 2 is here equipped with a pair of sliding blocks 21, 21 upon which a pair of binding posts 22, 22 are secured for the cords 17 17 and to the lower portions of said. blocks are secured metal rods 23, 23 which bear swivel posts 24, 24 upon their lower extremities. These posts have contact plates 25, 25 swiveled on the same, and intermediately upon the reduced portions 30, 3() of the' same are mounted leaf springs 26, 26 whose ends lie heavily against theicontact plates at 29, 29, etc. Upon the faces of these plates, cushions 27, 27 yare mounted, being preferably cemented thereto, while the lengths of tinfoil 28, 28 have their endsreadily caught under the ends 29, 29 of the leaf springs, for it is but necessary to lift one end 29 of the spring involved and pass the eXtreme end of the foil in under the same and then let the spring end fall back into place on the same, and the same operation repeated at the other end, to present a resilient metal surface upon the relatively flat pads of this smaller clamp. Replacing the foil is here only a moments work, for upon lifting first one end, and then the other of each leaf spring, the strip of foil can be withdrawn and new pieces set into place as already described.

It is manifest that if metal mesh is used, the same can be very easily removed for wash- .ing and disinfecting the ysame and when dry,

just as readily replaced in position again. However, it is preferred to usetinfoil or aluminum foil, replacing the same with new foilV frequently, and instead of covering either the foil or metal mesh with conducting solutions, it is also intended that the skin surface to be treated is instead to be more carefully wet just prior to the application of the pads or clamps thereto, thus avoiding any wetting of the mesh or foil. This also avoids all wetting of the cushion and any deterioration thereof. Even if it should be desired to wet the metal mesh, the same can now be so easily removed and through a sim'- ple and common manipulation cleaned and then replaced, that sanitary conditions and eiiicient operation of the device can be relied on to be permanent land satisfactory at all times.

Variations may be resorted to vand parts may be. used without others, and instead of sponge rubber for cushions, I may use chemits ically treated sponges or cotton cushions, etc: Y

Having now fully described my invention, I claim:

1. A contact pad for electro-therapeutic devices, including the combination, of a clamping plate having solely the ends thereof bent over to form retaining edges while the sides of said plate are Open, a resilient body normally disposed upon said clamping plate between said bent over edges and having the sides thereof exposed as well as the upper portion of the same, and a resilient contact means disposed upon said resilient body having the ends caught under .said bent over plate ends and the surface thereof exposed upon said resilient body between said plate ends.

2. A contact pad for electro-therapeutic devices, including the combination, of af clamping plate having solely two opposite ends thereof bent over to form retaining edges, a resilient cushion normally held upon said plate between said bent over` ends, the sides of said plate being open and exposing said cushion while the upper surface of the latter is exposed between said retaining edges, a resilient Contact means overlying the cushion and having the ends thereof caught under said retaining edges, and means associated with said resilient contact means and said retaining edges in order to releasably retain said contact means in assembled relation with said cushion and plate.

3. A contact pad for electro-therapeutic devices, including the combination, of a clamping plate having solely two opposite ends thereof bent over to form retaining edges while the sides of said plate are open, a resilient cushion disposed upon said clamping plate between said retaining edges having the top and sides thereof exposed, a resilient contact member overlying the upper surface of said cushion and having solely two ends thereof caught under said retaining edges while the surface thereof is exposed between said edges upon said cushion, and means including elongated members inserted with the ends of said contact means under said retaining edges in order to releasably retain said contact means in assembled relation to said cushion and clamping plate.

GUSTAV A. ZERNE. 

